I am working with a digital book application. I make use of swf loader to load swf pages created from pdf. I use TextSnapsot to draw inline text highlight on the pages. The highlight is thoroughly retained on the respective pages throughout the session and later it can be updated/deleted without any problem. Everything was working great till I made the following changes in the swf loading approach to enable page caching:
I am now loading swf loader object into application memory and while doing jumping from one page to other page I am just copying the content of the next page to the current swf loader which is on the display to the user. There are two sets of swf loaders - one for displaying the page and other to cache the next/previous page(s). On the caching side, I load the swf into application memory and after getting it loaded I pick all the contents of the loaded swf page (the children of it's movie clip) into an array collection. While changing the page I copy the cached content into the swf loader's movie clip which is displaying the page.
Now when I highlight on the page on display and navigate back/forth from the page and comeback again to the page where I did the highlighting: It shows the highlight I did. But as soon as I try to draw another highlight on that page, the previous highlight is instantly disappears from the page.
I suspect that the Textsnapshot object which draws highlight while navigating (to the target display page) is different from the one which redraws/update the highlight on the same page next time. Although the Textsnapshot object id for both the objects is same.
Here are some code snippet:
For copying the content from the swf loader object cached in application memory:
private function copyPageContent():void
{
var contentCollection:ArrayCollection = new ArrayCollection();
_pageContentVO = new PageContentVO();
_pageContentVO.contentHeight = MovieClip(_swfPageLoader.content).height;
_pageContentVO.contentWidth = MovieClip(_swfPageLoader.content).width;
var count:int = MovieClip(_swfPageLoader.content).numChildren;
for(var i:int=0;i<count;i++)
{
var dispObject:DisplayObject = MovieClip(_swfPageLoader.content).removeChildAt(0);
contentCollection.addItem(dispObject);
}
_pageContentVO.pageContentCollection = contentCollection;
_swfPageLoader = null;
}
For copying the content to the swf loader which is displaying the page:
private function copyContent(pageContentVo:PageContentVO):void
{
for(var i:int = 0;i<pageContentVo.pageContentCollection.length;i++)
{
var dispObject:DisplayObject = pageContentVo.pageContentCollection.getItemAt(i) as DisplayObject;
MovieClip(this.content).addChild(dispObject);
}
this.content.height = this.height;
this.content.width = this.width;
}
after this I dispatch swf loader's complete manually and in the handler of that event I take the text snap shot object.(highlightManager.as)
Code I use to draw highlight manually(using mouse drag on the page).
public function setHighlight():void
{
removeAll();
if(_textSnapShot!=null && _textSnapShot.getText(0,_textSnapShot.charCount)!="")
{
if(_isCoveredTextSelectedAtAnyInstance)
{
_textSnapShot.setSelected(_beginIndex,_endIndex+1,false); //this is the global variable to the class
}
else
{
_textSnapShot.setSelectColor(0xfff100);
_textSnapShot.setSelected(_beginIndex,_endIndex+1,true);
}
if(saveHighlight)
{
countHighlightedSegments();
}
}
}
Code I use to redraw previously drawn highlight when I return to the page:
public function showHighlights(textSnapShot:TextSnapshot,currentPageNum:int):void
{
if(currentPageNum >= 0)
{
textSnapShot.setSelected(0,textSnapShot.charCount,false);
var pageVO:PageVO = _model.eBookVO.eBookPagesVO.getItemAt(currentPageNum) as PageVO;
var objColl:ArrayCollection = new ArrayCollection();
objColl.source = pageVO.highLightSelection;
for(var i:int=0;i<objColl.length;i++)
{
var highlightVO:HighlightVO = new HighlightVO();
highlightVO.beginIndex = objColl.getItemAt(i).beginIndex;
highlightVO.endIndex = objColl.getItemAt(i).endIndex;
setHighlightedSegment(textSnapShot,highlightVO.beginIndex,highlightVO.endIndex);
}
}
}
private function setHighlightedSegment(textSnapShot:TextSnapshot,beginIndex:int,endIndex:int):void
{
textSnapShot.setSelectColor(0xfff100);
textSnapShot.setSelected(beginIndex,endIndex,true);
}
Looking forward to your support to resolve this issue.
Regards,
JS
